The invention relates generally to the control of haptic feedback in a manipulandum. More particularly, the invention relates to the control of haptic feedback in, for example, buttons or knobs.
In general, a button that is part of a system for generating tactile or haptic feedback to a user can be programmed with different force profiles to be output at the button. A haptic button may be programmed to have a variety of different “feels” depending on any number of variables, such as the state of the interface, the process to be controlled, and the number of positions in which the button can be moved.
In one known approach for implementing a haptic button, an active element (for example a direct-current (DC) motor) generates haptic feedback based on a detected motion of the button. This is a closed-loop type of feedback, because the haptic feedback output to a user is based solely on a position signal output from a sensor.
A need exists for a haptic button or knob system of reduced size relative to known devices. Additionally, a need exists for a system that produces haptic feedback to a manipulandum that enhances the mechanical “feel” of the manipulandum. Additional benefits may be realized using the methods and apparatus disclosed herein.